meaning of the const keyword appended to declarations
Hi, I'm looking at some of the overloaded declarations of member functions in classes.
They have a const, which I know means constant, appended to the end of the declaration. Can someone fill me in on what this means?
I know it means that if it begins with const... it's a constant... but I don't see why you would append one after the parameters in a declaration
example:
I'm used to seeing the type following the const keyword... meaning the variable stays the same always and can't be changed...
They have a const, which I know means constant, appended to the end of the declaration. Can someone fill me in on what this means?
I know it means that if it begins with const... it's a constant... but I don't see why you would append one after the parameters in a declaration
example:
int compare ( const string& str ) const;I'm used to seeing the type following the const keyword... meaning the variable stays the same always and can't be changed...
const keyword has a few uses in C++.
For your question you are asking the one in bold correct ? int compare ( const string& str ) const;
I only know their use if int compare is a member function inside a C++ class.
e.g
class Test {
public:
int compare(const string& str) const;
int compare(const string& str); //usually this version is provided also for callee to use
...
}
Above indicate compare member function can be called only by a constant object of class Test;
e.g
const Test i_am_constant; //assume default constructor is provided
//from here onwards i_am_constant if use it's member function are NOT allowed to modify the data members inside itself.
Think of it like const int i_am_constant_int = 0;
//from here onwards i_am_constant_int value cannot be changed any longer
For your question you are asking the one in bold correct ? int compare ( const string& str ) const;
I only know their use if int compare is a member function inside a C++ class.
e.g
class Test {
public:
int compare(const string& str) const;
int compare(const string& str); //usually this version is provided also for callee to use
...
}
Above indicate compare member function can be called only by a constant object of class Test;
e.g
const Test i_am_constant; //assume default constructor is provided
//from here onwards i_am_constant if use it's member function are NOT allowed to modify the data members inside itself.
Think of it like const int i_am_constant_int = 0;
//from here onwards i_am_constant_int value cannot be changed any longer
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